In recent years, there are increasing demands for reduction of fuel consumption of vehicles as part of countermeasures for preservation of the environment. As one of the countermeasures, weight reduction of a pneumatic tire is strongly required. Also, driving stability is required to be improved in accordance with the improvement of the performance of vehicles. In addition, the driving stability is desired to be improved without sacrificing driving comfortableness, which is tire performance conflicting with the driving stability.
In a conventionally known pneumatic tire, a two-layered carcass layer is provided between right and left bead portions so as to exhibit high movement performance. An example of such structure is disclosed in JP-A-2007-191044. Such a pneumatic tire is also required to reduce its weight and to improve the driving stability as described above, and techniques to obtain these advantages have been desired to be proposed.